ELI5: Explain Like I'm 5

Capital pi notation

Capital pi notation is a way to write down a bunch of multiplication problems all at once using a big letter that looks like a capital "P". It's like writing out a long list of numbers to be multiplied together, but instead of listing each number, you can just use one symbol that stands for all of them.

For example, if you wanted to multiply 2, 3, 4, and 5 together, you could use capital pi notation and write it like this:

∏(2, 3, 4, 5)

That means you need to multiply all of those numbers together. So, you would start with 2 and multiply it by 3 (to get 6), then multiply that by 4 (to get 24), and finally multiply that by 5 (to get 120). So, the answer is 120.

The great thing about capital pi notation is that it can save you a lot of time and space. Instead of writing out a long list of numbers to be multiplied, you can just use one symbol that stands for all of them. This can be really useful in math and science when you need to do a lot of multiplication quickly and efficiently.

Overall, capital pi notation is just a fancy way to write down a bunch of multiplication problems all at once. It looks like a big "P" and helps you save time and space by using one symbol to represent all of the numbers you need to multiply together.